In a communication device of a communication system, usually three main components are included: a service board, a backplane and a switch board, and signal interconnection between the service board and the switch board that is implemented through the backplane. With the increase of the access capacity of the communication device, the demand for the switching capacity of the backplane in the communication device gets higher and higher, and the backplane, as the core switching component of the communication device, bears switching planes of all the service boards and switch boards. In conventional backplane architecture, to implement large-scale service switching, the density of a physical interface gets larger and larger, and number of the service boards gets larger and larger, directly resulting in that the printed circuit board (PCB) wiring scale is very large, the number of layers increases continuously, and the size gets larger and larger. The processing limit has been reached, thereby forming a bottleneck for backplane design.
The conventional backplane in the prior art is one independent PCB plate, a backplane plane is perpendicular to a service board plane and a switch board plane, and all switching signals of the service board and a switch network board are borne by the backplane. In the implementation of the present application, the prior art has at least the following disadvantages: with the increase of the number of service boards, the size of the backplane is larger and larger, which is not beneficial for processing; and moreover, as the communication device requires a large switching capacity, due to the constraint of the limited size of the backplane, notch spacing needs to be reduced in exchange for installing a larger number of service boards, while a service signal between the service board and the switch board needs to perform PCB wiring through the notch spacing, so wiring space is compressed to the minimum, and the backplane has to rely on increasing the number of layers to implement large-scale service signal switching, resulting in a low yield and a high cost.